Shoe machinery



y 1942- L. s. LINDE'ROTH, JR 2,282,365

SHOE MACHINERY Filed May 5, 1959 3 Sheets-Sheet l Wat-6966.-

May 12, 1942. 1.. s. LINDEROTH, JR 2,282,365

SHOE MACHINERY Fiied May 5, 1939 3 Sheets-Sheet 3 Patented May 12, 1942SHOE MACHINERY Lambert S. Linderoth, Jr., Marblehead, Mass., as-

signor to United Shoe Machinery Corporation, Borough of Flemington, N.J., a corporation of New Jersey Application May5, 1939, Serial No.271,965

6 Claims. (Cl. 51-273) This invention relates to dust hoods, and isherein illustrated and described as embodied in a dust collecting systemsuitable for use in a shoe machine of the type known as repair outfitswhich are equipped with various buffing, scouring and trimming tools.Such a machine isdisclosed in an application for United States LettersPatent, Serial No. 248,801, filed December 31, 1938, in the name ofFrederick A. Prahl, Jr. The operation of the various tools abovementioned gives rise to considerable quantities of dust and chips, whichmust be continuously removed from the locality of operation. Suchremoval is usually accomplished by a suction draft apparatus having dusthoods associated with the tools. It is ordinarily impracticable andnearly everywhere forbidden by law to conduct dust-laden air from thedust hoods through long lines of piping and then to discharge it intothe atmosphere outside of the building. The usual practice is to filterthe dust from the air in which it has been entrained, and then todischarge the cleaned air into the room. It is desirable that a systemof this character be compact, that the cleaned air which is returned tothe atmosphere be substantially free of dust and that the powerrequirements be a minimum.

It is an object of the present invention to provide a dust hood capableof contributing to the efficiency and compactness of a dust collectingsystem of a type which, for example, may conveniently be used in a shoerepair machine.

In accordance with a feature of the invention, the mouths of the severalillustrated dust hoods are each provided with an outwardly flaredportion terminating in a flange which extends about the lower portion ofthe rotary tool and closely adjacent thereto on opposite sides. Thisflange prevents air from leaking forwardly around the inlet end of thehood and thereby lessening the force of the draft by aerodynami callyconstricting the inlet passage of the hood. The flange Fig. 1 is aperspective View of the improved dust collecting system;

Fig. 2 is a front elevation of the collecting system with the dust hoodsremoved;

Fig. 3 is a vertical sectional view taken on the line IIL-III of Fig. 2;

Fig. 4 is a vertical sectional view taken on the line IV--IV of Fig. 3;

Fig. 5 is a perspective view of one of the dust hoods shown in Fig. 1;and

Fig. 6 is an end elevation of the dust hood shown in Fig. 5.

The improved dust hoods are shown. in the drawings in association with aportion of the shoe repair machine disclosed in the aboveamene tionedapplication Serial No. 248,801. The frame and housing of the machine areshown herein in broken lines and together they constitute a cabinet-likestructure indicated by the reference numeral I0. The lower portion ofthe cabinetlike structure I0 is normally closed by a plurality ofremovable front panels ll, one of which is fragmentarily shown inFig. 1. Journaled in bearings carried by the frame In is a shaft 12 uponwhich are mounted three heel scouring wheels 14, a bottom scouring rollIS, a shank buffing tool [8, and a heel breast scouring tool 20. Themachine is also provided with a pair of edge trimming tools 22.Associated with eachv of the heel scouring wheels I4 is a dust hood 24.The bottom scouring roll IS, the shank buffing tool I8 and the heelbreast scouring tool 20 are provided with dust hoods 26, 28 and 30,respectively. A large draft opening 32 is provided in a rear wall of themachine casing in back of the edge trimming tools 22 to collect the dustresulting from the operation of these tools,. while a draft opening 34is provided in a shelf beneath the edge trimming tools to collect chips.All of the above-mentioned dust hoods and draft openings lead into asuction manifold 36 which extends lengthwise of the machine or parallelto the axis of the shaft [2. i This manifold is designed to have across'sectional area at any point along its length corresponding to thevolume of air flowing past that point.

Below the manifold 36 and directly connected thereto is an apparatus forseparating the heavier particles of dust from the current of air inwhich they are entrained. This apparatus is housed within a compartmentof the cabinetlike casing l0 and is supported by a bracket 31 carriedthereby. It comprises a substantially cylindrical casing 38 having itsaxis substantially parallel to that of the shaft l2. Access to theinterior of the casing may be had through a sliding panel 39. Aconnection 40 leads downwardly and also rearwardly from the manifold 36into an inlet opening 42 (Figs. 3 and 4) of the casing 38. The inletopening 42 is located at the upper portion of the casing rearwardly ofthe center line thereof to receive a current of air which is directedtangentially into the casing. It extends somewhat over half the lengthof the casing from a point beginning at the right hand end thereof. Inthe lower portion of the casing and extending substantially the fulllength thereof is a slot 44 (Figs. 3 and 4) through which particles ofdust may pass. This slot is positioned forwardly of the vertical centerline of the casing and is substantially diametrically opposite the inlet42. The cylindrical wall of the casing is flattened at the localityindicated by the reference numeral 45 to enable the dust to passtangentially through the slot 44. Beneath the casing 38 is a closedreceptacle 45 into which the dust slot 44 opens. The receptacle 45 hasfront,

mulates therein, said drawer: being. easily acces-' sible from the frontof the. machine upon removal ofthepanel II. f I 1 Within the casing 38and coaxial therewith is an open-ended frusto-conical baflle 52 whichserves also as an exit conduit, having a small reobserved that the heelscouring wheel I4 is positioned partly within the inlet end of the' dusthood. The dust hood has a pair of flat parallel lateral walls I4, one ofwhich appears in Figs. 5 and 6. These walls are spaced from the endfaces of the scouring wheel I4 with only a reasonable clearance. Thedust hood has an upper portion I5 hinged upon a pintle I6 to provideaccess to the wheel I4 for the purpose of replacing the abrasive coverthereof, The portion has lateral walls which are continuous with the'walls E4, and has a top wall 11 which is close to the ceiving end 54Within the casing and having a the large end of the bafiie 52 opens intoa'filter chamber secured against the right hand end of the casing 38.The right hand end of the casing .38 surrounding the large end ofthe'baffle 52 is sealed by an end wall 62. In the illustrated machinethe walls 58 and 52 are continuous with the left and right end walls-48respec tively of the receptacle 46. The filter chamber isprovided with aremovable panel 64 and contains a filter 65 or the type disclosedin-United" States Letters Patent No. 2,050,508, granted 'Au-.

gust 11, 1936, upon the application of Richard Strindberg. Fig.1, forthe purpose of clearer illustration, shows the upper portion of thefilter 65 as cut away. This filter may be removed from time to timethrough the opening normally closed by the panel 64 for purposes ofcleaning. i'A

passageway 66 leads from the right hand side ofv the filter chamber 60to the intake of a fan 68 driven from any suitable source of powerthrough a belt 10.. The fan 68 creates the necessary suction for drawingair through the entire dust collecting system and exhausts the clean airthrough an opening I2 into'the atmosphere. The casing, the filter andthe fan are spaced close to each other, not only for compactness, but toreduceto-a minimum the length of the path travelled by the air in itspassage through the system.

The above described dust separating appara tus is not claimed herein,but is disclosed and claimed in a co -pending application for LettersPatent of'the United States, Serial No. 392,430, filed May 8, 1941; inmy name as a continuation in part of the present application."

The construction of one of the dust hoods 24 'is'sh own m detailin-Figs; w 6. It will be periphery of the wheel, with allowance forclearance.

sage for air.

The walls I4 and I8 flare outwardly at the mouth or inlet end'in asmooth curve to form I a flange the outer extremity of which is flat.This fiat portion of the flange 8!] lies in a plane substantiallyparallel to the axis of the wheel I4 and intersects the wheel forwardlyof the axis. The flange 35 begins at a point adjacent to one end face ofthe wheel I4 at a less radial distance from the axis of the wheel thanthe pe-' riphery of the wheel and extends around the above-mentioned airinlet passage to a corresponding point adjacent to the opposite end faceof the wheel. It will be observed that the flange has a pair of lateraledges 84 (Fig. 5) which are parallel to the lateral walls 14 and a loweredge 86 which is substantially perpendicular to the edges 84. As shownin'Fig. 5, the plane'of the flange 89 is substantially normal to thedirection of the air inlet passage. It has been found that the flange 80is important inpreventing air. from leaking around the edges of the hoodand by reason of its sudden change in direction reducing the effectivecross-sectional area of the inlet passage, thereby diminishing theVolume of air drawn into the hood. The flange also causes substantiallyall of the incoming air to be drawn from in front of the hood,

and in such a manner as to insure the air current having a maximumvelocity directly in front of the hood and below the tool, at whichlocality the dust arising from the operation of the tool will be mosteffectively caught. The hood 3B is similar to the hood 24 except for itsbeing designed to fit a frusto-conical wheel rather than a cylindricalwheel.

In the operation of the system the fan 58 creates a suction at theopenings of the various dust hoods to draw into the manifold 36 air.

laden with dust arising from the operation of the tools. This air isthen delivered tangentially through the opening 42 into the casing 38and whirls about the axis of the casing in an annular passagewa definedby the baffle 52 and the wall of the casing. Gravity and centrifugalforce cause the heavier particles of dust to be thrown against thecurved wall of the casing until they pass tangentially through the slot44 into the dust drawer 59., The air with the finer particles of dustentrained therein passes into the small open end 54 of the bafile orconduit 52 and.

I is returned to the atmosphere by the fan 58. The

air retains a considerable amount of its rotary movement about the axis.of the casing while passing through the baffle 52.; Such rotary move,-

ment causes some of the entrained dust particles to be thrown againstthe inner wall of the baffie and eventually to be directed to the edgeand corner portions of the filter out of the direct path of the aircurrent, thereby enabling the entire area of the filter to be utilizedto better advantage by preventing premature cloggmg.

An advantage of the above-described dust collecting system resides inits compactness, enabling the dust separating apparatus and fan to behoused in a relatively small compartment. Although the volume of airpassing through the machine is relatively large, considering the smallsize of the separating apparatus, the power required for effectiveseparation is not excessive and is well within the limits imposed bypractical considerations in the shoe repair trade. A relatively smallamount of power is required to draw air through hoods of the characterabove described because the flanges of these hoods have the effect, forreasons already stated, of increasing the area of the inlet passage ofthe hoods while insuring a maximum velocity of the air at the localitywhere it is most desired. Some of the power thus saved at the hoods maybe utilized in the separating apparatus which, being of smalldimensions, calls for a greater expenditure of power to draw air throughit than would be required if it were larger. However, the separatingapparatus itself requires less power than its compactness might lead oneto expect. The preliminary separation of the heavier particles of dustenables a minimum area of filtering material to be employed. Thearrangement of the frusto-conical bafile in the cylindrical casingprovides for separation of these heavier particles in a minimum of spacewhile at the same time enabling the otherwise waste space at the cornersof the filter chamber to be utilized. The frusto-conical shape of thebaflle 52 is important inasmuch as it provides an annular passage ofsuflicient cross-sectional area for the air entering the casing While atthe same time it delivers air over a larger area and at a lower velocitythan if it were cylindrical. The various features of the machine allcooperate to permit the separating apparatus to .be housed thereinwithout materially increasing its dimensions or the required power to anextent commerciallyprohibitive.

Having described my invention, what I claim as new and desire to secureby Letters Patent of the United States is:

1. In combination with a rotary abrading tool, a dust hood havinglateral walls which are spaced closely to the end faces of said toolwith allowance for reasonable clearance, said hood having also a bottomwall spaced from the periphery of said tool to provide a passage forincoming air, said walls being arranged to form a mouth into which saidtool extends, and said hood being provided at its mouth with anoutwardly flared extension of said walls terminating in an outwardlyturned flange which extends continuously about the lower portion of therotary tool and about said air inlet passage.

2. In combination with a rotary abrading tool, a dust hood having an airinlet end and an end adapted for connection to a. suction system, saidhood terminating at said inlet end in an outwardly extending flangewhich lies in a plane parallel to the axis of said tool and whichintersects said tool, said hood having lateral walls which are spacedclosely to the end faces of said tool with allowance for reasonableclearance, said hood having also a bottom wall spaced from the peripheryof said tool to provide a passage for the incoming air, and said flangebeing continuous around said passage except at the 10- cality occupiedby said tool.

3. In combination with a rotary abrading tool, a dust hood having an airinlet end and an end adapted for connection to a suction system, saidhood terminating at said inlet end in a flange which lies in a planeparallel to the axis of said tool and which intersects said tool, saidhood having at its inlet end portion a pair of parallel lateral wallsbetween which said tool is located, said walls being closely spaced tothe end faces of said tool with allowance for reasonable clearance, saidhood having also at its inlet end portion a bottom wall spaced from theperiphery ofsaid tool to provide a passage for the incoming air, saidflange being continuous around said passage except at the localityoccupied by said tool, and said walls at the inlet'end portion of saidhood flaring smoothly outwardly into said flange.

4. In combination with a rotary abrading tool, a dust hood having an airinlet end and an end adapted for connection to a suction system, saidabrading tool being positioned at and partly within said inlet end witha minimum clearance between the end faces of the tool and the hood, saidhood having at the inlet end portion a top wall spaced closely to theperiphery of said tool with allowance for clearance and a bottom wallspaced from the periphery of said tool to provide a passage for incomingair, said hood at said inlet end flaring smoothly into an outwardlyturned flange which extends downwardly from a point adjacent to one endface of the tool around said passage for incoming air and then upwardlyto a point adjacent to the opposite end face of the tool.

5. In combination with a rotary abrading tool, a dust hood having an airinlet end and an end adapted for connection to a suction system, saidhood having at its inlet end portion a pair of parallel lateral wallsbetween which said tool is located, said walls being closely spaced tothe end faces of said tool with allowance for reasonable clearance, saidhood having also at its inlet end portion a bottom wall spaced from theperiphery of said tool to provide a passage for the incoming air, saidhood at its inlet end flaring outwardly to form a flange which iscontinuous around said passage except at the locality occupied by saidtool, said flange terminating in a pair of edges which are parallel toeach other and to said lateral walls and in an edge joining saidparallel edges.

6. A dust hood having a mouth into which a rotary abrading tool mayextend, said mouth comprising a pair of lateral walls adapted to bespaced closely to the end faces of said tool with allowance forreasonable clearance, and comprising also a bottom wall adapted to bespaced from the periphery of said tool to provide an air inlet passagebelow the tool, said walls having outwardly flared portions terminatingin an outwardly turned flange which extends continuously around thelocality to be occupied by the lower portion of the abrading tool andabout said air inlet passage, said flange lying in a plane substantiallynormal to the direction of said inlet passage.

LAMBERT S. LINDEROTH, JR.

